Question: Simplify the expression. $ (-2x^{7}+3x^{3}) - ( -7x^{7}-x^{4}+2x^{3}) $
Answer: Distribute any negative signs. $(-2x^{7}+3x^{3}) + (7x^{7}+x^{4}-2x^{3})$ Since we are adding polynomials, we can simply remove the parentheses. $-2x^{7}+3x^{3} + 7x^{7}+x^{4}-2x^{3}$ Identify like terms. $ - {2 x^7} + {3 x^3} + {7 x^7} + \color{#DF0030}{ x^4} - {2 x^3} $ Combine like terms. $ { ( -2 + 7 ) x^7} + \color{#DF0030}{ x^4} + { x^3} $ Add the coefficients. $5x^{7}+x^{4}+x^{3}$